This invention relates to novelty slub yarns produced by combining false-twisted continuous filament yarns in one or more air jets.
Processes for producing such yarns are known. For example, U.S. Pat. No. 4,351,148 discloses a method to form a slub yarn by combining a core and effect yarn in a jet wherein the slubs are allowed to form by controlling the path length of the effect yarn using a mechanical deviation device which periodically lengthens the effect yarn's path while the core yarn is supplied directly to the jet at a constant linear velocity. The yarn produced comprises a plurality of slubs produced along its length with a characteristic nub produced at the tail of each slub.